 (declare series
          update-key)
 
+; A Series is a data structure that maps an index
 ; A Series is a data structure that maps an index
 ; to valus.  It supports:
 ; - Order 1 access to values by index

    frame with a new row added corresponding
    to the input index and column map."
    (if (contains? this idx)
      (update-key this idx val)
      (series (conj values val) (conj index idx)))))

; Constructor

  to the input index"
  ([^Series srs i] (get srs i nil))
  ([^Series srs i or-else] (get srs i or-else)))


(defn set-index
